Sgrew-driver



yHFAHRNM,` SCREW DRIVER.

(No Model.)

No. 572,800. Patented Dec. 8'1896- ESSE Vl Du UNITED STATES f PATENT OFFICE.

HIRAM F. HENRY, OF CLEVELAND, OHIO.

SCREW-DRIVER.

SPECIFICATION forming part of Letters Patent No. 572,800, dated December 8, 1896.

Application filed March 25, 1896.

Awithout requiring adjusting of the parts.

The invention consists of certain parts and details and combinations of the same, as will be fully described hereinafter and then pointed out in the claims.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the iigures.

Figure l is a sectional side elevation of the improvement, showing the parts in a normal or disengaged position. Fig. 2 is a sectional side elevation of the same with the teeth in mesh. Fig. 3 is a side elevation of Jthe same with the cap in section, and Fig. 4 is an inverted plan view of the handle.

The improved screw-driver is provided with a handle A, formed at its lower end with a spindle A and iittinginto a correspondinglyshaped recess B, formed in the upper end of the shank B, provided at its lower end with the usual bit B2 for engagement with the slot in the screw. The upper end of the shank B is formed with a head B3, made cylindrical and provided at the top with teeth B4, adapted to be engaged by correspondinglyshaped teeth A3, formed on the under side of the lower threaded part A2 of the handle, said threaded part being engaged by a cap C, engaging the lower reduced part of the head B3 to hold the latter in place in the cap and to permit vertical movement of the head in said cap. The teeth A3 and B4 are held normally out of mesh, and for this purpose I employ a coil-spring D, set with its lower end in an annular recess B5, formed in the top of the head B3, the upper end of the spring extending into a similar recess A4, formed in the under side of the threaded Serial No. 584,864. (No model.)

part A3 of the handle'A. Now it will be seen that by the arrangement described the spring D normally holds the handle A and shank B out of mesh at their teeth A3 and B4,` respectively,but when the bit B2 is engaged with the slot in the screwand a longitudinal pressure is given to the handle A then the teeth A3 are moved in mesh with the teeth B4, so that the operator upon turning the handle A rotates the shank B to drive the screw inward or outward, according to the direction in which the handle A is turned.

When the operator has given a turn to the handle A for screwing or unscrewing, and he desires to repeat it, then he slightly releases the longitudinal pressure on the handle without, however, disengaging the bit B3 from the slot in the screw. As soon as the pressure on the handle is reduced the spring D forces the handle A outward to move the teeth A3 out of mesh with the teeth B4, to permit of returning the handle A to its former position without the operator releasing the grip .on the handle and without disengaging the bit B2 from the slot in the screw.

It will be seen that this screw-driver is very simple and durable in construction and permits of readily and effectively working the handle forward and backward without disengaging the shank from the screw-slot and without requiring an adjustment of the parts.

By forming the shank B with the recess B the handle A may be left solid, thus preventing the weakening of the wooden handle by forming a recess therein. On the other hand, the metal shank B can well stand the weakening effect of producing the recess.

By fitting the opposite ends of the spring in annular recesses formed, respectively, in the handle and in the shank such ends of the spring are securely held and all breaking and y bending of the spring is avoided, every coil being in the construction shown held at some part at all times in either the recess of the handle or that of the shank, as shown most clearly in Fig. 2.

Having thus fully described my invention, I claim as new and desire to secure by Letters Patentl. The tool herein described consisting of the handle having at its lower end a central IOO `downwardly-projected spindle, having at its inner or upper end an annular enlargement and an annular recess surrounding such enlargement and having surrounding such recess a flange having the series of teeth, the tool-shank having in its upper end a socket to receive the spindle of the handle, having a flange surrounding the upper end of such socket and inclosing an annular recess separated from the socket and coincident with the recess in the lower end of the handle, said flange having a series of teeth in position for engagement by those of the handle, the spring fitted at its opposite ends in the recesses in the handle and tool-shank and devices connecting the handle and shank, substantially as shown and described.

2. The tool herein described consisting of the handle havingy atits lower end a central downwardly-projectedspindle having at its inner or upper end. an annular enlargement and an. annular recess surrounding such enlargement and having surrounding such recess a flange having the series of teeth, the tool-shank having in its upper end a socket to receive the spindle ofv the handle, having a flange surrounding the upper end of such socket and inclosing an annular recess sepiarated from the socket and coincident with the recess in the lower end of the handle, said flange having a series of teeth in position for engagement by those of the handle, the spring fitted at its opposite ends in the recesses in the handle and tool-shank and the tool-shank having an enlarged portion surrounding -its 

